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<p class="MsoNormal">There are a number of hooks to control this in PrologEpilogInserter spread between TargetFrameLowering and TargetRegisterInfo. The one you most want to look at is probably TargetRegisterInfo::requiresFrameIndexScavenging.<o:p></o:p></p>
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<p class="MsoNormal">-Matt<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">llvm-dev <llvm-dev-bounces@lists.llvm.org> on behalf of llvm-dev <llvm-dev@lists.llvm.org><br>
<b>Reply-To: </b>Joan Lluch <joan.lluch@icloud.com><br>
<b>Date: </b>Friday, May 3, 2019 at 7:50 PM<br>
<b>To: </b>llvm-dev <llvm-dev@lists.llvm.org><br>
<b>Subject: </b>[llvm-dev] LLVM Virtual registers after RA pass?<o:p></o:p></span></p>
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<p class="MsoNormal">I need to use ‘createVirtualRegister’ for a specific case in my ‘eliminateFrameIndex’ function implementation.
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<p class="MsoNormal">However, whenever that code is executed, I get the assertion "MachineCopyPropagation should be run after register allocation!” at a later stage.<o:p></o:p></p>
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<p class="MsoNormal">I have seen that at least a couple of backend implementations (including ARM Thumb) create virtual registers in ‘eliminatedFrameIndex’.<o:p></o:p></p>
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<p class="MsoNormal">What am I missing?, is there something that I need to set for virtual registers to be allowed after the RA pass, and specifically in the ‘eliminateFrameIndex’ function?<o:p></o:p></p>
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<p class="MsoNormal">Thanks,<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:9.0pt;font-family:Helvetica;color:black">Joan Lluch<br>
Puigsacalm, 7 <br>
17458 - Fornells de la Selva<br>
Girona<br>
<br>
Tel: 620 28 45 13<o:p></o:p></span></p>
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